 <template>
    <div>
      <div class="shopcart">
          <div class="content" @click="toggleList">
              <div class="content-left">
                  <div class="logo-wrapper" >
                      <div class="logo" :class="{'highlight':totalCount >0}">
                          <i class="icon-shopping_cart" :class="{'highlight':totalCount >0}"></i>
                      </div>
                      <div class="num" v-show="totalCount>0">{{totalCount}}</div>
                  </div>
                  <div class="price" :class="{'highlight':totalPrice >0}">￥{{totalPrice}}</div>
                  <div class="desc">另需配送费￥{{ deliveryPrice }}元</div>
              </div>
              <div class="content-right" @click.stop.prevent="pay">
                  <div class="pay" :class="payClass">
                      {{payDesc}}
                  </div>
              </div>
          </div>
          <div class="ball-container">
            <div v-for="(ball,index) in balls" :key="index">
              <transition name="drop" @before-enter="beforeDrop" @enter="dropping" @after-enter="afterDrop">
                <div class="ball" v-show="ball.show">
                  <div class="inner inner-hook"></div>
                </div>
              </transition>
            </div>
          </div>
          <transition name="fold">
            <div class="shopcart-list" v-show="listShow" >
              <div class="list-header">
                <h1 class="title">购物车</h1>
                <span class="empty" @click="empty">清空</span>
              </div>
              <div class="list-content" ref="listContent">
                <ul class="food-ul">
                  <li v-for="(food,index) in selectFoods" class="food" :key="index">
                    <span class="name">{{food.name}}</span>
                    <div class="price">
                      <span>￥{{food.price * food.count}}</span>
                    </div>
                    <div class="cartcontrol-wrapper">
                      <cartcontrol :food="food"></cartcontrol>
                    </div>
                  </li>
                </ul>
              </div>
            </div>
          </transition>
      </div>
      <transition name="fade">
        <div class="list-mask" @click="hideList" v-show="listShow"></div>
      </transition>
    </div>
 </template>

<script>
import cartcontrol from '../cartcontrol/cartcontrol'
import BScroll from 'better-scroll'
export default{
  props: {
    selectFoods: {
      type: Array,
      default () {
        return [{
          price: 10,
          count: 1
        }]
      }
    },
    deliveryPrice: {
      type: Number,
      default: 0
    },
    minPrice: {
      type: Number,
      default: 0
    }
  },
  data () {
    return {
      balls: [
        {
          show: false
        },
        {
          show: false
        },
        {
          show: false
        },
        {
          show: false
        },
        {
          show: false
        }
      ],
      dropBalls: [],
      fold: true
    }
  },
  watch: {
    fold: function () {
      let show = !this.fold
      if (show) {
        this.$nextTick(() => {
          if (!this.scroll) {
            this.scroll = new BScroll(this.$refs.listContent, {
              click: true
            })
          } else {
            this.scroll.refresh()
          }
        })
      }
    }
  },
  computed: {
    totalPrice () {
      let total = 0
      this.selectFoods.forEach((food) => {
        total += food.count * food.price
      })
      return total
    },
    totalCount () {
      let count = 0
      this.selectFoods.forEach((food) => {
        count += food.count
      })
      return count
    },
    payDesc () {
      if (this.totalPrice === 0) {
        return `${this.minPrice}元起送`
      } else if (this.totalPrice < this.minPrice) {
        let diff = this.minPrice - this.totalPrice
        return `还差${diff}元起送`
      } else {
        return `结算`
      }
    },
    payClass () {
      if (this.totalPrice < this.minPrice) {
        return 'not-enough'
      } else {
        return 'enough'
      }
    },
    listShow () {
      if (!this.totalCount) {
        return false
      }
      return !this.fold
    }
  },
  methods: {
    drop (el) {
      for (let i = 0; i < this.balls.length; i++) {
        let ball = this.balls[i]
        if (!ball.show) {
          ball.show = true
          ball.el = el
          this.dropBalls.push(ball)
          return
        }
      }
    },
    beforeDrop (el) {
      let count = this.balls.length
      while (count--) {
        let ball = this.balls[count]
        if (ball.show) {
          let rect = ball.el.getBoundingClientRect()
          let x = rect.left - 32
          let y = -(window.innerHeight - rect.top - 22)
          el.style.display = ' '
          el.style.webkitTransform = `translate3d(0,${y}px,0)`
          el.style.transform = `translate3d(0,${y}px,0)`
          let inner = el.getElementsByClassName('inner-hook')[0]
          inner.style.webkitTransform = `translate3d(${x}px,0,0)`
          inner.style.transform = `translate3d(${x}px,0,0)`
        }
      }
    },
    dropping (el, done) {
      /* eslint-disable no-unused-vars */
      let rf = el.offsetHeight
      this.$nextTick(() => {
        el.style.webkitTransform = 'translate3d(0,0,0)'
        el.style.transform = 'translate3d(0,0,0)'
        let inner = el.getElementsByClassName('inner-hook')[0]
        inner.style.webkitTransform = 'translate3d(0,0,0)'
        inner.style.transform = 'translate3d(0,0,0)'
        el.addEventListener('transitionend', done)
      })
    },
    afterDrop (el) {
      let ball = this.dropBalls.shift()
      if (ball) {
        ball.show = false
        el.style.display = 'none'
      }
    },
    toggleList () {
      if (!this.totalCount) {
        return
      }
      this.fold = !this.fold
    },
    empty () {
      this.selectFoods.forEach((food) => {
        food.count = 0
      })
    },
    hideList () {
      this.fold = true
    },
    pay () {
      if (this.totalPrice < this.minPrice) {
        return
      }
      window.alert(`支付${this.totalPrice}元`)
    }
  },
  components: {
    cartcontrol
  }
}
</script>

<style lang="stylus">
@import '../../common/stylus/mixin.styl'
    .shopcart
        position fixed
        bottom 0
        left 0
        width 100%
        z-index 50
        height 48px
        .content
            display flex
            background #141d27
            .content-left
                flex 1
                .logo-wrapper
                    display inline-block
                    vertical-align top
                    position relative
                    top -10px
                    margin 0 12px
                    padding 6px
                    width 56px
                    height 56px
                    box-sizing border-box
                    border-radius 50%
                    background #141d27
                    .num
                        position absolute
                        top 0
                        right 0
                        height 16px
                        width 24px
                        line-height 16px
                        text-align center
                        border-radius 16px
                        font-size 9px
                        font-weight 700
                        color #fff
                        background rgb(240,20,20)
                        box-shadow 0 4px 8px 0 rgba(0,0,0,0.4)
                    .logo
                        width 100%
                        height 100%
                        border-radius 50%
                        background #2b343c
                        text-align center
                        &.highlight
                         background rgb(0,160,220)
                        .icon-shopping_cart
                            line-height 44px
                            font-size 24px
                            color #80858a
                            &.highlight
                                color #fff
                .price
                    display inline-block
                    vertical-align top
                    margin-top 12px
                    line-height 24px
                    padding-right 12px
                    box-sizing border-box
                    border-right 1px solid rgba(255,255,255,0.1)
                    font-size 16px
                    font-weight 700
                    color rgba(255,255,255,0.4)
                    &.highlight
                        color #fff
                .desc
                    margin-top 12px
                    display inline-block
                    vertical-align top
                    margin-left 12px
                    line-height 24px
                    font-size 10px
                    color rgba(255,255,255,0.4)
            .content-right
                flex 0 0 105px
                width 105px
                .pay
                    font-size 12px
                    height 48px
                    line-height 48px
                    text-align center
                    color rgba(255,255,255,0.4)
                    fonr-weiht 700
                    &.not-enough
                      background #2b333b
                    &.enough
                      background #00b43c
                      color: #fff
        .ball-container
          .ball
            position fixed
            left 32px
            bottom 22px
            z-index 200
            transition: all 0.4s cubic-bezier(0.49, -0.29, 0.75, 0.41)
            &.drop-transition
              transition all 0.4s
            .inner
              display inline-block
              width 16px
              height 16px
              border-radius 50%
              background rgb(0,160,220)
              transition all 0.4s linear
        .shopcart-list
          position absolute
          z-index -1
          top 0
          left 0
          width 100%
          transform translate3d(0, -100%, 0)
          &.fold-enter-active, &.fold-leave-active
            transition all 0.5s
          &.fold-enter, &.fold-leave-active
            transform translate3d(0,0,0)
          .list-header
            height 40px
            line-height 40px
            padding 0 18px
            background #f3f5f7
            border-bottom 1px solid rgba(7,17,27,0.1)
            .title
              float left
              font-size 14px
              color rgb(7,17,27)
            .empty
              float right
              font-size 12px
              color rgb(0,160,220)
          .list-content
            padding 0 18px
            max-height 217px
            overflow hidden
            background #fff
            .food-ul
              list-style-type none
              padding 0
              margin-top 0
              .food
                position relative
                padding 12px 0
                box-sizing border-box
                border-1px(rgba(7,17,27,0.1))
                .name
                  line-height 24px
                  font-size 14px
                  color rgb(7,17,27)
                .price
                  position absolute
                  right 90px
                  bottom 12px
                  line-height 24px
                  font-size 14px
                  font-weight 700
                  color rgb(240,20,20)
                .cartcontrol-wrapper
                  position absolute
                  right 0
                  bottom 6px
    .list-mask
      position fixed
      top 0
      left 0
      width 100%
      height 100%
      z-index 40
      opacity 1
      backdrop-filter blur(10px)
      background rgba(7,17,27,0.6)
      &.fade-enter-active, &.fade-leave-active
        transition all 0.5s
      &.fade-enter, &.fade-leave-active
        opacity 0
        background rgba(7,17,27,0)

</style>
